Enigma Reloaded 2016, September 17 to October 1, will promote Amateur Radio and celebrate the history of the Enigma cipher machine and its crucial role in the outcome of World War II.

The annual event, now in its 3rd year, takes place in two stages. September 17-30, Amateur Radio stations registered as Activator stations will be on the air. On October 1, the event’s final day, Activator stations will exchange CW messages previously encrypted by a real or emulated Enigma machine.

The cryptic rules and details are available on the official website.